1. Field of the Invention
The present invention relates to an electric device socket provided with a large number of contact pins for electrical connection with a large number of pin-shaped or spherical-shaped terminals arranged in the form of a matrix on the bottom surface of an electric device such as an integrated circuit (IC) package, more particularly relates to an improvement of an open top type socket which causes the contact pins to move between a contact position and a non-contact position with respect to terminals of the electric device by lateral movement of a moving plate with respect to a base member.
2. Description of the Related Art
Japanese Unexamined Patent Publication (Kokai) No. 4-19979 discloses an open top type socket configured so as to cause contact pins having a spring property to move between a contact position and non-contact position with respect to terminals of an IC package by lateral movement of a moving plate. This type of conventional socket is provided with a base member on which a large number of contact pins are arranged in the form of matrix corresponding to the arrangement of the terminals of the IC package, a moving plate provided on this base member so that lateral movement is possible, and an operation lever serving as an actuation member for laterally moving this moving plate. A large number of through holes through which terminals of the IC package and contact pins are passed are arranged in the form of a matrix on the moving plate. The operation lever exhibits a gate shape. The two leg portions of the operation lever are attached to the two ends of a support shaft extending passing between the two side surfaces of end portions of the base member and, at the same time, connected to the two ends of a transmission shaft extending passing between the two side surfaces of the end portions of the moving plate. Further, an upper end portion of the operation lever is located above the other end portions of the base member and moving plate. In this type of socket, when the upper end portion of the operation lever is depressed by an operation member provided so as to be vertically moveable with respect to the base member, the operation lever laterally moves the moving plate via the transmission shaft by the lever principle, therefore the contact pins can be moved from the contact position to the non-contact position with respect to the terminals of the IC package against a spring force thereof.
In the above conventional IC use socket, it is necessary to secure the operation stroke of the operation lever for laterally moving the moving plate a predetermined amount or more, therefore the leg portions of the operation lever must be arranged at the outside of the two side surfaces of the moving plate. For this reason, it is difficult to secure enough strength of the operation lever, so the operation of the operation lever is apt to become unstable. Further, the depression force of the operation member act concentratedly upon the two ends of the transmission shaft passing through the end portions of the moving plate via the two leg portions of the operation lever, therefore it is difficult to smoothly operate the moving plate.
On the other hand, in the IC use socket disclosed in Japanese Unexamined Patent Publication (Kokai) No. 57-41280, the lateral movement plate for moving the contact pins arranged in the form of a matrix between the contact position and non-contact position with respect to the terminals of the IC package is divided into a plurality of sliding plates.
This type of divided sliding plate has end portions formed as knife edges and pushes and makes a pressing sliding member run along a guide groove so as to sequentially move the sliding plate and switch on/off the contact pins.
In the above conventional IC use socket, since the lateral movement plate is divided into a plurality of sliding plates, the on/off switching operation of the contact pins can be easily carried out, but the pressing sliding member must be attached or detached in a lateral direction and the amount of actuation of the pressing sliding member is large, so there are the problems that the operability is poor and application to automatic machines is difficult. Further, the necessity of performing the on/off switching operation of the contact pins by two different end portions becomes a cause lowering the operability by automatic machines.
Accordingly, an object of the present invention is to provide an socket for an electric device capable of stably operating a moving plate for moving contact pins from a contact position to a non-contact position with respect to terminals of an electric device to be mounted and actuation members for laterally moving the moving plate and, in addition, excellent in operability.
To attain the above object, the present invention provides an electric device socket characterized in that provision is made of a base member on which a large number of contact pins for contact with terminals of an electric device are arranged in the form of a matrix, a moving plate provided laterally moveably with respect to the base member and engaged with the contact pins, an operation member provided vertically moveably with respect to the base member, and at least one actuation member engaged with an end portion of the moving plate and receiving an actuation force of the operation member so as to act so as to laterally move the moving plate at the time of depression of the operation member, the actuation member being arranged along the end surface of the moving plate.
In the electric device socket having the above configuration, since the actuation member engaged with the end portion of the moving plate is arranged along the end surface of the moving plate, the actuation force of the operation member can be dispersed along the end surface of the moving plate via the actuation member when made to act upon the end portion of the moving plate. Accordingly, the moving plate can be smoothly laterally moved by the actuation force dispersed along the end surface thereof. Further, the actuation member can be arranged effectively utilizing a lateral width in a direction orthogonal to the direction of lateral movement in the end portion of the moving plate, therefore concentration of stress to the actuation member can be prevented and the operational stability and durability of the actuation member can be easily enhanced. In addition, the actuation member can be operated by the vertical movement of the operation member with respect to the base member, therefore the operability is excellent and application to an automatic machine becomes easy.
Preferably, the actuation member is engaged with an end portion of the moving plate via a transmission shaft passing through the end portion of the moving plate in a direction orthogonal to the direction of lateral movement.
According to the above configuration, the actuation force dispersed by an actuation member can be made to act upon the moving plate via the transmission shaft. Further, since a transmission shaft passing through the end portion of the moving plate in a direction orthogonal to the direction of lateral movement is used, the engagement structure between the actuation member and the moving plate can be simplified and the assembly work can be facilitated.
Preferably, the transmission shaft is divided into a plurality of sections in a direction orthogonal to the direction of lateral movement of the moving plate.
According to the above configuration, since the transmission shaft is divided into a plurality of sections, permanent strain of the shaft etc. can be prevented in comparison with the case where the transmission shaft is constituted by a single piece over the entire length and the service life of the transmission shaft can be prolonged. Further, a latch member for engaging with another actuation member, for example, the mounted electric device, can be arranged in the space between shaft sections, therefore the socket configuration can be effectively utilized.
Preferably, actuation members are engaged with opposite end portions of the moving plate, respectively, so as to perform a pressing or pulling action in the direction of lateral movement of the moving plate.
According to the above configuration, the actuation force of the operation member can be made to act upon the two end portions of the moving plate via the actuation member performing a pressing action upon one end portion of the moving plate and the actuation member performing the pulling action with respect to the other end portion of the moving plate, therefore the moving plate can be further smoothly laterally moved along the opposite end surfaces thereof by respectively dispersed actuation forces.
Preferably, each actuation member comprises a single actuation plate, and the actuation plate has three or more engagement portions engaged with the end portions of the moving plate.
According to the above configuration, the actuation force of the operation member can be made to act upon the end portions of the moving plate by reliably dispersing it by the three or more engagement portions of the actuation plates.
Preferably, each actuation member has a plurality of actuation plates which are connected to each other and constitute a toggle mechanism.
According to the above configuration, a large actuation force for laterally moving the moving plate can be obtained from the actuation force given from the operation member to the actuation members, therefore the operation member can be operated by a light force.
Preferably, each actuation member comprises a plurality of independent units arranged along an end portion of the moving plate, and the units can individually actuate so as to laterally move the moving plate when receiving the actuation force of the operation member.
According to the above configuration, the actuation force of the operation member can be dispersed by a plurality of units and made to individually act upon the end portion of the moving plate. Further, the units can individually actuate, therefore even if a variation occurs in timing etc. of receiving the actuation force from the operation member, the variation can be absorbed in an initial stage by the individual actuation of units. Accordingly, thereafter, a uniform actuation force can be made to act upon the moving plate.
Preferably, each unit comprises a single actuation plate.
According to the above configuration, the actuation force of the operation member is reliably dispersed wide along the end surfaces of the moving plate by the actuation plates of the units and can be made to act upon the end portions of the moving plate.
Preferably, each unit has a plurality of actuation plates which are connected to each other and constitute a toggle mechanism.
According to the above configuration, a large actuation force for laterally moving the moving plate can be obtained from the actuation force given from the operation member to the actuation plates of the units, therefore the operation member can be actuated by a light force.
Preferably, the moving plate comprises a plurality of plate pieces arranged in a direction orthogonal to the direction of lateral movement thereof.
According to the above configuration, by changing the combination of the number of plate pieces, electric device socket having different numbers of contact pins can be easily manufactured.